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Effective mass of elementary excitations in Galilean-invariant integrable models

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 نشر من قبل Michael Pustilnik
 تاريخ النشر 2016
  مجال البحث فيزياء
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We study low-energy excitations of one-dimensional Galilean-invariant models integrable by Bethe ansatz and characterized by nonsingular two-particle scattering phase shifts. We prove that the curvature of the excitation spectra is described by the recently proposed phenomenological expression for the effective mass. Our results apply to such models as the repulsive Lieb-Liniger model and the hyperbolic Calogero-Sutherland model.

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